HHS Special Exposure Cohort Determination:

Chapman Valve Manufacturing Company (Bldg 23 and the Dean Street Facility)

HHS Determination Concerning a Petition to Add Members to the 

Special Exposure Cohort 

under the 

Energy Employees Occupational Illness Compensation Program Act of 2000 

Determination Concerning a Petition for Employees from 

Chapman Valve Manufacturing Company

Indian Orchard, Massachusetts

(Building 23 and the Dean Street Facility)
HHS Special Exposure Cohort Determination:

Chapman Valve Manufacturing Company (Bldg 23 and the Dean Street Facility)

I. Determination 

I, Kathleen Sebelius, Secretary of Health and Human Services (Secretary), have determined 

that the employees defined in Section II of this report do not meet the statutory criteria for 

addition to the Special Exposure Cohort (SEC), as authorized under the Energy Employees 

Occupational Illness Compensation Program Act of 2000 (EEOICPA), 42 U.S.C. § 7384q.

___June 3, 2011_____ _[Signature on file]_________________

Date Kathleen Sebelius

II. Employee Class Definition

All Atomic Weapons Employees who were monitored, or should have 

been monitored, for radiological exposures while performing Atomic 

Energy Commission work at the Chapman Valve Manufacturing 

Company (i.e., Building 23 and the Dean Street facility) in Indian 

Orchard, Massachusetts, from January 1, 1948 through December 31, 

1949, and from January 1, 1991 through December 31, 1993.

III. Decision Criteria and Recommendations

Pursuant to 42 U.S.C. § 7384q, to designate a class for addition to the SEC, the Secretary 

must determine, upon recommendation of the Advisory Board on Radiation and Worker 

Health (Board), that

(1) it is not feasible to estimate with sufficient accuracy the radiation dose that the class 

received; and

(2) there is a reasonable likelihood that such radiation dose may have endangered the 

health of members of the class.

The SEC final rule states in 42 C.F.R. § 83.13(c)(1) that it is feasible in two situations to 

estimate the radiation dose that the class received with sufficient accuracy. First, the rule 

states that radiation doses may be estimated with sufficient accuracy if NIOSH has 

established that it has access to sufficient information to estimate the maximum radiation 

dose for every type of cancer for which radiation doses are reconstructed that could have 

been incurred under plausible circumstances by any member of the class. Alternatively, 

radiation doses may be estimated with sufficient accuracy if NIOSH has established that it 

has access to sufficient information to estimate the radiation doses of members of the class 

more precisely than a maximum dose estimate.

In a letter received by the Secretary on March 30, 2011, the Board, pursuant to 42 U.S.C. § 

7384q, agreed with the following NIOSH findings, effectively advising the Secretary that 

radiation dose can be reconstructed with sufficient accuracy for certain Chapman Valve 

Manufacturing Company employees in accordance with provisions of EEOICPA and the 

SEC final rule.
HHS Special Exposure Cohort Determination:

Chapman Valve Manufacturing Company (Bldg 23 and the Dean Street Facility)

IV. Determination Findings

Feasibility of Estimating Radiation Doses with Sufficient Accuracy

The Secretary established the feasibility determination for the class of employees covered 

by this report based upon the findings summarized below.

• NIOSH determined that the only source term information that existed at Chapman for all 

periods evaluated in the Evaluation Report was natural uranium. Recycled uranium did 

not enter process streams until 1952, so no recycled uranium would have been 

processed at Chapman during the 1948 to 1949 operational period. 

• NIOSH determined that for the operational period from January 1, 1948 through April 30, 

1949, radioactive materials could have become airborne as a result of activities and 

practices associated with the machining of uranium, including a 1948 uranium fire. The 

principal source of internal radiation exposure was from natural uranium dust produced 

from the manipulation of oxidized metal during machining and related processes and 

from exposure during the documented fire. 

• After the operations were completed, intakes of radioactive material were also possible 

during the residual period from May 1, 1949 through December 31, 1949, and from 

January 1, 1991 through December 31, 1993 because of exposures associated with the 

remaining residual radioactive material. NIOSH has access to sufficient radiation survey 

data to estimate intakes of uranium during the residual period. 

• NIOSH has access to sufficient bioassay results and radiation data to estimate all 

workers’ internal exposure to uranium for the evaluated time periods. For unmonitored 

workers during the operational period or unmonitored periods (i.e., the residual period), 

the Chapman Valve Technical Basis Document1 analyzes the bioassay results to

provide estimates of co-workers’ uranium intakes. 

• The principal source of external radiation doses during the operational period was 

natural uranium and its short-lived progeny in the form of metal rods. NIOSH has 

determined that adequate film badge results are available to estimate doses for Atomic 

Weapons Employees who worked during the 1948 to 1949 period. Further, an upper

bound of external dose based on film badge dosimetry records can be used to 

reconstruct doses for unmonitored workers. 

• NIOSH has access to beta and gamma survey data that can be used to reconstruct 

external radiation doses to workers during the residual contamination period.

• Although information regarding whether or not occupationally-required medical X-ray 

examinations were performed at Chapman Valve during the operational period is 

unavailable, and no records have been identified indicating that occupational medical Xrays were required during the operational period, the dose associated with X-ray exams 

 

1 ORAUT-TKBS-0033, Technical Basis Document for the Chapman Valve Manufacturing Company, Indian Orchard, 

Massachusetts. Revision 02, September 12, 2008.
HHS Special Exposure Cohort Determination:

Chapman Valve Manufacturing Company (Bldg 23 and the Dean Street Facility)

can be assessed using the methodology defined in ORAUT-OTIB-0006, Dose 

Reconstruction from Occupationally Related Diagnostic X-Ray Procedures.

• NIOSH determined that it has access to sufficient information to bound internal and 

external dose for all members of the evaluated class during both the operational and 

residual periods.

In its letter to the Secretary, the Board concurred with these NIOSH findings.

Health Endangerment

Because the Secretary established that it is feasible to estimate with sufficient accuracy the 

radiation doses encountered by Chapman Valve Manufacturing Company employees as 

specified in this class, a determination of health endangerment is not required.

V. Effect of the Determination

Members of the class of employees covered by this determination and their survivors 

continue to be eligible to submit claims for compensation under EEOICPA. As required for 

cancer claims covering other DOE and Atomic Weapons Employer employees (or Atomic 

Weapons Employees) not included in the SEC, qualified cancer claims under Part B of 

EEOICPA for members of this class will be adjudicated by the Department of Labor, in part 

on the basis of radiation dose reconstructions which will be conducted by NIOSH.

VI. Administrative Review of Determination

The determination provided in this report may be subject to an administrative review within 

HHS, pursuant to 42 C.F.R. § 83.18(a). On the basis of such a review, if the Secretary 

decides to designate the class of employees covered by this determination, in part or in 

whole, as an addition to the SEC, the Secretary would transmit a new report to Congress 

providing the designation and the criteria and findings on which the decision was based.